[NET]: Annotate callers of csum_fold() in net/*

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c
index b39a37a..cb9da08 100644
--- a/net/ipv4/icmp.c
+++ b/net/ipv4/icmp.c
@@ -356,7 +356,7 @@
 		ip_flush_pending_frames(icmp_socket->sk);
 	else if ((skb = skb_peek(&icmp_socket->sk->sk_write_queue)) != NULL) {
 		struct icmphdr *icmph = skb->h.icmph;
-		unsigned int csum = 0;
+		__wsum csum = 0;
 		struct sk_buff *skb1;
 
 		skb_queue_walk(&icmp_socket->sk->sk_write_queue, skb1) {
@@ -931,7 +931,7 @@
 
 	switch (skb->ip_summed) {
 	case CHECKSUM_COMPLETE:
-		if (!(u16)csum_fold(skb->csum))
+		if (!csum_fold(skb->csum))
 			break;
 		/* fall through */
 	case CHECKSUM_NONE:
diff --git a/net/ipv4/igmp.c b/net/ipv4/igmp.c
index 6eee716..0017ccb 100644
--- a/net/ipv4/igmp.c
+++ b/net/ipv4/igmp.c
@@ -932,7 +932,7 @@
 
 	switch (skb->ip_summed) {
 	case CHECKSUM_COMPLETE:
-		if (!(u16)csum_fold(skb->csum))
+		if (!csum_fold(skb->csum))
 			break;
 		/* fall through */
 	case CHECKSUM_NONE:
diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c
index 2522114..2bf54ade 100644
--- a/net/ipv4/ip_gre.c
+++ b/net/ipv4/ip_gre.c
@@ -557,7 +557,7 @@
 	struct iphdr *iph;
 	u8     *h;
 	__be16    flags;
-	u16    csum = 0;
+	__sum16   csum = 0;
 	__be32 key = 0;
 	u32    seqno = 0;
 	struct ip_tunnel *tunnel;
@@ -580,7 +580,7 @@
 		if (flags&GRE_CSUM) {
 			switch (skb->ip_summed) {
 			case CHECKSUM_COMPLETE:
-				csum = (u16)csum_fold(skb->csum);
+				csum = csum_fold(skb->csum);
 				if (!csum)
 					break;
 				/* fall through */
diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
index 90942a3..5f3e35c 100644
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -1384,7 +1384,7 @@
 		       &ipc, rt, MSG_DONTWAIT);
 	if ((skb = skb_peek(&sk->sk_write_queue)) != NULL) {
 		if (arg->csumoffset >= 0)
-			*((u16 *)skb->h.raw + arg->csumoffset) = csum_fold(csum_add(skb->csum, arg->csum));
+			*((__sum16 *)skb->h.raw + arg->csumoffset) = csum_fold(csum_add(skb->csum, arg->csum));
 		skb->ip_summed = CHECKSUM_NONE;
 		ip_push_pending_frames(sk);
 	}
diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c
index 97cfa97..efcf45e 100644
--- a/net/ipv4/ipmr.c
+++ b/net/ipv4/ipmr.c
@@ -1493,7 +1493,7 @@
         if (pim->type != ((PIM_VERSION<<4)|(PIM_REGISTER)) ||
 	    (pim->flags&PIM_NULL_REGISTER) ||
 	    (ip_compute_csum((void *)pim, sizeof(*pim)) != 0 && 
-	     (u16)csum_fold(skb_checksum(skb, 0, skb->len, 0)))) 
+	     csum_fold(skb_checksum(skb, 0, skb->len, 0))))
 		goto drop;
 
 	/* check if the inner packet is destined to mcast group */
diff --git a/net/ipv4/ipvs/ip_vs_core.c b/net/ipv4/ipvs/ip_vs_core.c
index 1445bb4..fac2dff 100644
--- a/net/ipv4/ipvs/ip_vs_core.c
+++ b/net/ipv4/ipvs/ip_vs_core.c
@@ -538,7 +538,7 @@
 
 u16 ip_vs_checksum_complete(struct sk_buff *skb, int offset)
 {
-	return (u16) csum_fold(skb_checksum(skb, offset, skb->len - offset, 0));
+	return csum_fold(skb_checksum(skb, offset, skb->len - offset, 0));
 }
 
 static inline struct sk_buff *
diff --git a/net/ipv4/netfilter.c b/net/ipv4/netfilter.c
index e49441a..b797a37 100644
--- a/net/ipv4/netfilter.c
+++ b/net/ipv4/netfilter.c
@@ -172,7 +172,7 @@
 	case CHECKSUM_COMPLETE:
 		if (hook != NF_IP_PRE_ROUTING && hook != NF_IP_LOCAL_IN)
 			break;
-		if ((protocol == 0 && !(u16)csum_fold(skb->csum)) ||
+		if ((protocol == 0 && !csum_fold(skb->csum)) ||
 		    !csum_tcpudp_magic(iph->saddr, iph->daddr,
 			    	       skb->len - dataoff, protocol,
 				       skb->csum)) {
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index dadef86..168f9de 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -2162,7 +2162,7 @@
 	struct tcphdr *th;
 	unsigned thlen;
 	unsigned int seq;
-	unsigned int delta;
+	__be32 delta;
 	unsigned int oldlen;
 	unsigned int len;
 
@@ -2215,7 +2215,8 @@
 	do {
 		th->fin = th->psh = 0;
 
-		th->check = ~csum_fold(th->check + delta);
+		th->check = ~csum_fold((__force __wsum)((__force u32)th->check +
+				       (__force u32)delta));
 		if (skb->ip_summed != CHECKSUM_PARTIAL)
 			th->check = csum_fold(csum_partial(skb->h.raw, thlen,
 							   skb->csum));
@@ -2229,7 +2230,8 @@
 	} while (skb->next);
 
 	delta = htonl(oldlen + (skb->tail - skb->h.raw) + skb->data_len);
-	th->check = ~csum_fold(th->check + delta);
+	th->check = ~csum_fold((__force __wsum)((__force u32)th->check +
+				(__force u32)delta));
 	if (skb->ip_summed != CHECKSUM_PARTIAL)
 		th->check = csum_fold(csum_partial(skb->h.raw, thlen,
 						   skb->csum));